The prevalence of childhood obesity has tripled over the last three decades, and ethnic minority and low- income children are disproportionally affected. Improving the school nutrition environment has the potential to reach disadvantaged children, yet little is known about the impact of the school nutrition environment on preventing obesity and reducing disparities. Understanding the relationship of the school nutrition environment to child obesity is important for addressing ways to improve dietary behaviors that are likely to prevent obesity and obesity-related co-morbidities such as hyperlipidemia and diabetes. I am pursuing a K01 Mentored Research Scientist Development Award to fill critical training gaps in the areas of school nutrition, health disparities, and longitudinal statistical methods. My career goal is to develop, implement, evaluate, and disseminate school-based nutrition interventions to promote nutritional health and reduce the risk of obesity within vulnerable populations. My detailed training plan includes formal coursework at UCSF and UC Berkeley, meetings, seminars, readings, and research apprenticeships. Through the proposed series of studies, I will determine which school nutrition programs and policies are associated with overweight and obesity and examine how disparities in access might underlie obesity patterns within the NIH-funded (NHLBI-led) Healthy Communities Study. My primary hypothesis is that higher intensity efforts to improve school nutrition environments, defined by duration, reach, and behavioral strategy, will have healthier weight children compared to lower intensity school nutrition environments, and this will differ by income and race/ethnicity. In preparation fo submitting an R01 grant application to test this hypothesis, I will first identify trends in the intensity of school nutrition programs and policies over a 10-year period in a national evaluation of elementary and middle schools in diverse communities. Second, I will examine the associations between the current school nutrition environment and children's weight status by income and race/ethnicity. Finally, I will determine whether the combination of a supportive school nutrition environment and school nutrition education is associated with improved weight status. These findings will be innovative because it will be the first critical step in identifying which school nutrition programs and policies are most effective for obesity prevention across a diverse set of socioeconomic factors to better inform public health practice. The proposed training plan and series of studies will provide me with a set of skills and expertise needed to successfully compete for R01 funding and to serve as a leader in the field of school-based interventions to prevent childhood obesity and reduce health disparities.